Abstract: A standard calibration solution includes water, a non-alcoholic solvent that is mixed with water, and a steroid hormone, and a content of the non-alcoholic solvent is 10% by volume or more and 50% by volume or less. The standard calibration solution is used for quantitative measurement using a mass spectrometry device.

Abstract: An oil supply device includes: an oil pump; an oil supply flow passage through which oil discharged from the oil pump flows; and an air mixing portion that cools a cooling object by mixing air into the oil supplied to the oil supply flow passage and supplying the oil mixed with the air to the cooling object.

Abstract: An image forming apparatus sequentially transfers toner images formed on a plurality of photosensitive drums onto an intermediate transfer member or a transfer material to form an image. The image forming apparatus includes an intermediate transfer belt provided with electrical conductivity, and a power supply for applying a voltage to a secondary transfer roller to pass a current from the secondary transfer roller to the plurality of photosensitive drums via the intermediate transfer belt, thus primarily transferring the toner images from the plurality of photosensitive drums onto the intermediate transfer belt.

Abstract: An image forming apparatus sequentially transfers toner images formed on a plurality of photosensitive drums onto an intermediate transfer member or a transfer material to form an image. The image forming apparatus includes an intermediate transfer belt provided with electrical conductivity, and a power supply for applying a voltage to a secondary transfer roller to pass a current from the secondary transfer roller to the plurality of photosensitive drums via the intermediate transfer belt, thus primarily transferring the toner images from the plurality of photosensitive drums onto the intermediate transfer belt.

Abstract: An image forming apparatus sequentially transfers toner images formed on a plurality of photosensitive drums onto an intermediate transfer member or a transfer material to form an image. The image forming apparatus includes an intermediate transfer belt provided with electrical conductivity, and a power supply for applying a voltage to a secondary transfer roller to pass a current from the secondary transfer roller to the plurality of photosensitive drums via the intermediate transfer belt, thus primarily transferring the toner images from the plurality of photosensitive drums onto the intermediate transfer belt.

Abstract: The present invention relates to an image forming apparatus that forms an image by consecutively superposing toner images that have been formed on a plurality of photosensitive drums, on an intermediate transfer member or a transfer medium. The image forming apparatus is made compact and operates at a low cost. Since a current supply member supplies a current in a rotational direction of an intermediate transfer belt, multiple first transfer portions do not need corresponding voltage sources. Even in the case where a charging member supplies a current, the potential of the intermediate transfer belt is maintained at a predetermined potential by a constant-voltage element connected to support rollers.

Abstract: An image forming apparatus sequentially transfers toner images formed on a plurality of photosensitive drums onto an intermediate transfer member or a transfer material to form an image. The image forming apparatus includes an intermediate transfer belt provided with electrical conductivity, and a power supply for applying a voltage to a secondary transfer roller to pass a current from the secondary transfer roller to the plurality of photosensitive drums via the intermediate transfer belt, thus primarily transferring the toner images from the plurality of photosensitive drums onto the intermediate transfer belt.

Abstract: The present invention relates to an image forming apparatus that forms an image by consecutively superposing toner images that have been formed on a plurality of photosensitive drums, on an intermediate transfer member or a transfer medium. The image forming apparatus is made compact and operates at a low cost. Since a current supply member supplies a current in a rotational direction of an intermediate transfer belt, multiple first transfer portions do not need corresponding voltage sources. Even in the case where a charging member supplies a current, the potential of the intermediate transfer belt is maintained at a predetermined potential by a constant-voltage element connected to support rollers.

Abstract: A developing roller that is capable of carrying toner on a surface thereof, and that supplies the toner carried on the surface to a surface of a photosensitive drum when a voltage is applied thereto, includes: a rubber layer; and a surface layer that covers the rubber layer, contains alumina, and has a higher volume resistivity than the rubber layer.

Abstract: It has been difficult to ensure satisfactory secondary transfer performance while ensuring satisfactory primary transfer performance by passing a current in the circumferential direction of an intermediate transfer belt from a current supply member. To satisfy a relationship of Rv>Rs, where Rv is resistance in the thickness direction of an intermediate transfer belt and Rs is resistance in the circumferential direction of the intermediate transfer belt over the distance between an image carrier located most upstream and an image carrier located most downstream in the movement direction of the intermediate transfer belt.

Abstract: An image forming apparatus sequentially transfers toner images formed on a plurality of photosensitive drums onto an intermediate transfer member or a transfer material to form an image. The image forming apparatus includes an intermediate transfer belt provided with electrical conductivity, and a power supply for applying a voltage to a secondary transfer roller to pass a current from the secondary transfer roller to the plurality of photosensitive drums via the intermediate transfer belt, thus primarily transferring the toner images from the plurality of photosensitive drums onto the intermediate transfer belt.

Abstract: The present invention relates to an image forming apparatus that forms an image by consecutively superposing toner images that have been formed on a plurality of photosensitive drums, on an intermediate transfer member or a transfer medium. The image forming apparatus is made compact and operates at a low cost. Since a current supply member supplies a current in a rotational direction of an intermediate transfer belt, multiple first transfer portions do not need corresponding voltage sources. Even in the case where a charging member supplies a current, the potential of the intermediate transfer belt is maintained at a predetermined potential by a constant-voltage element connected to support rollers.

Abstract: An image forming apparatus sequentially transfers toner images formed on a plurality of photosensitive drums onto an intermediate transfer member or a transfer material to form an image. The image forming apparatus includes an intermediate transfer belt provided with electrical conductivity, and a power supply for applying a voltage to a current supply member contacting the outer circumferential surface of the intermediate transfer belt to pass a current from the current supply member to the plurality of photosensitive drums via the intermediate transfer belt, thus primarily transferring the toner images from the plurality of photosensitive drums onto the intermediate transfer belt.

Abstract: An image forming apparatus sequentially transfers toner images formed on a plurality of photosensitive drums onto an intermediate transfer member or a transfer material to form an image. The image forming apparatus includes an intermediate transfer belt provided with electrical conductivity, and a power supply for applying a voltage to a current supply member contacting the intermediate transfer belt to pass a current from the current supply member to the plurality of photosensitive drums via the intermediate transfer belt, thus generating electric discharge on the upstream side of each of primary transfer sections.

Abstract: A developing roller that is capable of carrying toner on a surface thereof, and that supplies the toner carried on the surface to a surface of a photosensitive drum when a voltage is applied thereto, includes: a rubber layer; and a surface layer that covers the rubber layer, contains alumina, and has a higher volume resistivity than the rubber layer.

Abstract: It has been difficult to ensure satisfactory secondary transfer performance while ensuring satisfactory primary transfer performance by passing a current in the circumferential direction of an intermediate transfer belt from a current supply member. To satisfy a relationship of Rv>Rs, where Rv is resistance in the thickness direction of an intermediate transfer belt and Rs is resistance in the circumferential direction of the intermediate transfer belt over the distance between an image carrier located most upstream and an image carrier located most downstream in the movement direction of the intermediate transfer belt.

Abstract: It has been difficult to ensure satisfactory secondary transfer performance while ensuring satisfactory primary transfer performance by passing a current in the circumferential direction of an intermediate transfer belt from a current supply member. To satisfy a relationship of Rv>Rs, where Rv is resistance in the thickness direction of an intermediate transfer belt and Rs is resistance in the circumferential direction of the intermediate transfer belt over the distance between an image carrier located most upstream and an image carrier located most downstream in the movement direction of the intermediate transfer belt.

Abstract: The present invention relates to an image forming apparatus that forms an image by consecutively superposing toner images that have been formed on a plurality of photosensitive drums, on an intermediate transfer member or a transfer medium. The image forming apparatus is made compact and operates at a low cost. Since a current supply member supplies a current in a rotational direction of an intermediate transfer belt, multiple first transfer portions do not need corresponding voltage sources. Even in the case where a charging member supplies a current, the potential of the intermediate transfer belt is maintained at a predetermined potential by a constant-voltage element connected to support rollers.

Abstract: An image forming apparatus includes a first index forming unit that forms a plurality of first electrostatic latent image indexes at positions adjacent to a toner image to be formed on a recording material in a width direction of a first image bearing member and a second index forming unit forms a plurality of second electrostatic latent image indexes at positions adjacent to a toner image to be formed on the recording material in a width direction of a second image bearing member. A control unit controls operation of at least a second image forming unit so as to maintain a set positional relationship between the first electrostatic latent image indexes transferred to an intermediate transfer member and the second electrostatic latent image indexes based on detection results by first and second detection units.

Abstract: It has been difficult to ensure satisfactory secondary transfer performance while ensuring satisfactory primary transfer performance by passing a current in the circumferential direction of an intermediate transfer belt from a current supply member. To satisfy a relationship of Rv>Rs, where Rv is resistance in the thickness direction of an intermediate transfer belt and Rs is resistance in the circumferential direction of the intermediate transfer belt over the distance between an image carrier located most upstream and an image carrier located most downstream in the movement direction of the intermediate transfer belt.